It is necessary in hospital and other medical environments to sterilize medical instruments with steam or ethylene oxide. Various types of sterilization containers for medical instruments have therefore been developed. One such container comprises a plastic hermetically sealed housing having a tray disposed therein for receiving and organizing medical instruments. Filtered inlet and outlet ports are located on the top and bottom surfaces of the housing to permit the flow of steam through the container. The container is stackable and, thus in use, a plurality of such containers may be disposed within a steam sterilizer and arranged therein in a stack. That arrangement permits more instruments to be sterilized per sterilization cycle, thus lowering the sterilization cost per instrument. This process has, however, suffered from various disadvantages.
By way of explanation, steam sterilizers are normally designed so that steam enters the chamber of the sterilizer through an inlet port located at the top of the unit. As steam enters, colder air in the sterilizer is pressed toward the bottom of the sterilizer chamber and eventually exits the sterilizer through an outlet port located on the bottom surface of the sterilizer. When a plurality of sterilization containers are stacked within the sterilizer, steam entering the sterilizer chamber will enter the inlet port of the topmost sterilization container in the stack and be discharged through the outlet port of that container. The discharged steam will then enter the inlet port of the container located immediately therebeneath and will in turn enter and be discharged from each of the containers in the stack.
As steam successively enters each of the containers, it comes into contact with the medical instruments located in the container and gradually cools off. Thus, the discharged air and condensate will be colder than the original fresh steam and accordingly less effective in the sterilization process. Further, the steam becomes less sterile as it passes through succeeding containers. As the number of stacked containers increases, the problem of ineffective sterilization necessarily also increases. Prior containers have also often been designed so that condensate tends to collect within the containers instead of draining therefrom. The need has thus arisen for a plastic sterilization container which is stackable and which also enables the effective and economical sterilization of medical instruments.